单选题The new drug will not be put on the market ______ it has proved safe on humans.

单选题Most pupils in China are too shy to speak ______.

单选题______most school teachers were men, but today there are more women than men. A. At once B. At one time C. At present D. At the time

单选题People in our village respected him because he was a doctor with a ______ position in society.

单选题A smell of newly ______ bread comes from the kitchen.

单选题Kyle doesn"t like white coffee, nor does he like to put cream on his strawberries, because he prefers them ______.

单选题Not everybody believed his claim that he was innocent.

单选题It never occurred to me ______ you could succeed in persuading him to change his mind.

单选题 (D) The way in which memory takes place is not known. Some psychologists (心理学家) think that there is a physical change in the brain ceils or nerves when learning takes place. Psychologists are also unable to say what makes people forget. Some things are forgotten quickly while others are always remembered. Sometimes a person seems to have forgotten certain material completely, yet is able to relearn the material more quickly than when he first learned it. In trying to understand memory, psychologists have done a lot of experiments. Psychologists have found that the conditions under which something is learned have an effect on how well it is remembered. When a great deal of material is to be learned, for example, to learn one thing at a time is better than to learn many things at a time. A person then learns more quickly and remembers better. Learning two similar things one after the other seems to have a bad effect on memory. When a person memorizes two sets of historical dates, one after the other, for example, he may mix up the two--the learning of new material prevents the remembering of the already learned material. Most forgetting takes place in the first day or so after learning. After that, forgetting happens more slowly. Material that is understood--such as ideas or riddles (谜语)--is not so easily forgotten. Very little forgetting takes place in time if an idea is well understood. The more meaningful the learned material is, the better it will be remembered.

单选题The poor mother was anxious with suspicion that her son was really guilty as charged.

单选题Mary"s father has agreed ______ her marrying John.

单选题He is ______ a writer.

单选题That's the course ______. A. what I'm interested in B. which I'm fond on C. I'm interested in D. of that I'm fond

单选题Silence is unnatural to man. He begins his life with a cry and 1 it in stillness. In the 2 he does all he can to make a noise and there are few things of which he stands in more fear than the 3 of noise. Even his conversation is in great measure a desperate attempt to 4 a dreadful(糟透的，讨厌的) silence. If he is introduced to someone, and a number of 5 occur in the conversation he regards himself as a failure and is full of 6 of the empties-headed chatterbox. He knows that 99% of human conversation means no more than the buzzing(嗡嗡声) of a fly, but he 7 to join in the buzz, and to 8 that he is a man and not a wax-work figure. The 9 of a conversation is usually not to communicate ideas, but to 10 up all the buzzing sound. 11 , most buzzing is agreeable to the ear, and some of it is agreeable to the 12 . A man would be very 13 if he waited until he had a wise thought before taking part in the buzzing with others. Those who despise (鄙视，看不起) the weather as a conversational 14 seem to me to be 15 of the reason why human beings wish to talk. 16 , very few human beings join in a conversation in which they are 17 allowed to go on making a noise into other people"s ears, though they have nothing to tell them 18 that they have seen two or three new plays or 19 they have had bad food in a Swiss hotel. At the end of the evening during which they have said nothing meaningful 20 immense length they congratulate themselves on their success as talkers.

单选题Most laboratory and field studies of human behavior ______ taking a situational photograph at a given time and in a given place.

单选题

单选题Because of the strong sun the new sitting-room curtains have ______ from dark blue to grey.

单选题I don"t remember the boiler ______ during these years.

单选题They had talked only for a few minutes ______ they found they were of different opinions.

单选题Mr. White has three children, all ______ have become professors. A. of whom B. of which C. of them D. of those